Can Republicans take control of the US Senate in November? One Republican PAC thinks the path is wide open, and perhaps wider than some may think. According to their polling, Republican challengers lead or tie with current Democratic incumbents in six states already, and in two more Democrats are so weak as to be in serious trouble.  American Crossroads CEO Steven Law sent out this memo earlier today:

Virtually all Democrat incumbents in red states and purple states are in trouble – either down or tied in head-to-head contests with their likely GOP opponents, or upside down in approval ratings:

• In Arkansas, Republican Tom Cotton leads incumbent Democrat Sen. Mark Pryor 42-36. Pryor’s job approval is upside-down, with 37% approving and 40% disapproving of the way he is handling his job as senator.
• In Alaska, Democrat Sen. Mark Begich trails both major GOP candidates, Mead Treadwell and Dan Sullivan, by six points (47-41). Begich is also upside-down, with 47% disapproving of his job as senator, and 41% approving.
• In Montana, GOP Rep. Steve Daines leads Democrat Lt. Gov. John Walsh by 14 points (43-29) – and leads former Lt. Gov. John Bohlinger by 43-32%.
• Louisiana voters do not like Mary Landrieu. 51% disapprove of the way she is handling her job, with only 40% favorable. AMAZINGLY, while she generates 42% support on the initial ballot in Louisiana (Louisiana has an open initial ballot where if no one gains 50% support, a two-candidate ballot follows) she only moves to 44% in a head-to-head against likely GOP candidate, Rep. Bill Cassidy. Cassidy leads a head to head 45-44, with 11% not sure. (Fully 46 percent of voters don’t have an opinion on Cassidy.)
• In Michigan, Republican Terri Lynn Land leads Democrat Rep. Gary Peters 42-37 – while President Obama is underwater in his approval rating 38%-52%.
• In North Carolina, Democrat Kay Hagan is viewed by 37% favorably and 49% unfavorably. She ties likely GOP candidate Thom Tillis 44-44.
• Finally, in New Hampshire, Democrat Sen. Jean Shaheen leads former Sen. Scott Brown 40-35% in a hypothetical matchup – even as she is one of the few democratic incumbents with a net positive impression among her voters. Dragging her down to 40 in the head-to-head? The 22% net disapproval for President Obama (57-35) and a staggering 28% disapproval of the Obamacare law, with 60% disapproving of it and only 32% approving of the law.

Let’s start by reminding everyone that interest-group polling — at least those results that get released — usually supports the position of the interest group. American Crossroads, a PAC that raises money and campaigns for Republicans, does a lot of polling as part of their work. That doesn’t mean the polls are wrong, but it’s information that people need to keep in mind as part of their credibility. And it’s still very early in the cycle to get too sanguine about a wave election coming, even if the portents look strong.

What makes this a little more compelling is another analysis from earlier in the week by Chris Cillizza at the Washington Post. A major factor in midterm elections is the standing of the President among the various constituencies in play. Cillizza looked at Barack Obama’s approval rating in the states that will elect Senators in this cycle — and the news looks even worse for Democrats than American Crossroads suggests:

If the 2014 election is a referendum on President Obama, Democrats are in deep trouble.

That’s according to a new state-by-state study of Obama’s job-approval ratings released by Gallup that puts his disapproval rating at over 50 percent in 10 of the 21 states where Democrats are defending Senate seats this fall. In many of those states, Republicans have recruited strong candidates and are preparing to spend big bucks to win the six seats they need to regain the majority.

Obama is deeply unpopular — with a disapproval rating higher than 55 percent — in five states: West Virginia (67.3 percent disapproval), Montana (60.9 percent), South Dakota (59.3 percent), Arkansas (57 percent) and Alaska (55.4 percent).

Beyond those five seats, there is a second tier of states where the president’s disapproval rating stands somewhere between 50 percent and 55 percent, including: Iowa (50.1 percent disapproval), New Hampshire (50.2 percent), North Carolina (50.4 percent), Colorado (51.2 percent) and Louisiana (53.9 percent).

Colorado doesn’t get a mention from American Crossroads, but Quinnipiac suggests that Mark Udall will have big trouble holding his seat. He’s in a statistical tie with Tea Party candidate Ken Buck and several other potential Republican challengers:

With large gender gaps, Colorado voters approve 45 – 41 percent of the job Sen. Mark Udall is doing, but are divided 42 – 42 percent on whether he deserves reelection this year. Women approve 51 – 32 percent and say 48 – 31 percent he deserves reelection. Men disapprove 49 – 40 percent and say 52 – 36 percent he does not deserve reelection.

Looking at the 2014 U.S. Senate race in Colorado, Sen. Udall gets 45 percent to 42 percent for Republican District Attorney Ken Buck. In other possible matchups:

• Udall gets 43 percent to 41 percent for State Sen. Randy Baumgardner;
• Udall edges State Sen. Owen Hill 44 – 39 percent;
• Udall has 43 percent to State Rep. Amy Stephens with 41 percent;
• Udall tops businessman Jaime McMillan 45 – 38 percent.

“Democratic incumbent U.S. Sen. Mark Udall may be the front-runner, but he can hear the footsteps of three challengers, all within a few percentage points of him,” Malloy said.

Obama’s approval rating in Colorado from Quinnipiac explains this. He’s currently 22 points underwater at 37/59, which means Udall’s doing well just to stay in the mid-40s. On the other hand, Mitch McConnell’s looking a little weak in Kentucky, so Republicans may have to work harder to extend their competitive stance.

If this does turn out to be a referendum on Obama, then American Crossroads will almost certainly be correct. But that depends on the GOP keeping the focus on ObamaCare and executive incompetence and arrogance, rather than on themselves in party-splitting agendas.