Marco Rubio has extended his re-election polling lead in the Mason-Dixon series, demonstrating the good fortune of the GOP from his change of heart. Rubio now leads challenger Rep. Patrick Murphy by seven, up from three points in the last M-D survey, and leads everywhere in the state except for deep-blue southeast Florida — and by wide majorities in all but one other region. Hispanic voters are “the key to Rubio’s success,” and what differentiates him from the top of the ticket:

Republican incumbent Marco Rubio was increased his lead over Democratic challenger Patrick Murphy in the Florida Senate race. Statewide, 47% of likely voters support Rubio, while 40% back Murphy, Libertarian Paul Stanton draws 5%, 2% are split among the other four candidates on the ballot and 6% are still undecided. In late August, before the state primary election, Rubio held only a narrow 46%-43% advantage.

The Rubio campaign has been successful in raising Murphy’s negative rating, which now stands at 27% favorable/25% unfavorable. In August it was 30% favorable/11% unfavorable. Rubio’s own numbers are stronger (45% favorable/34% unfavorable) and have not significantly changed since last month.

The key to Rubio’s success is his ability to run stronger than the average Republican among Hispanic voters. Currently, Hispanics favor Rubio over Murphy 53%-38%, which is helping him pull 16% of Democratic voters. It is extremely difficult now for a Democrat to win in Florida while losing the Hispanic vote. In the presidential race, for example, Hillary Clinton’s margin over Donald Trump with Hispanics (64%- 29%) is the primary reason she is currently holding a slight statewide lead.

The favorability ratings are of particular interest. Rubio has a +11, a very good number for an incumbent, but Murphy still has a +2 despite a pretty significant attack on his credibility and the exposure of his resumé padding. More people are neutral on Murphy (33%) than either negative or positive, but the fact that Murphy hasn’t gone underwater is perhaps a glint of hope for Democrats.

If so, it’s only a glint. The rest of the demos look bad, and the sample might have made them look better than they actually are. It has 41% Democrats to 39% Republicans and only 20% independents, which is far off from 2012’s 35/33/32 and 2014’s 31/35/35. Rubio leads among independents by eight points, 46/38, so that may be a significant difference regardless of which turnout model one prefers.

The ethnic demos fall right into line with both elections, though, and Rubio is winning whites 52/33 and Hispanics 53/38, as noted above. Rubio only draws 9% of black voters, but Murphy only has 77% of their support, with 13% undecided. Unless Murphy can win them all, he’s in very big trouble. Rubio also wins the gender battle with a +14, almost breaking even with Murphy among women (42/44) and winning big among men (52/36). Other than southeast Florida, where Rubio trails by 16 points, the only other area of the state where he doesn’t win a majority is in the Tampa area — where he leads by six, 46/40. In other words, this looks like a solid lead, and a missed opportunity for Democrats.

It’s not the only one, either. Mason-Dixon’s presidential poll puts Hillary Clinton up four over Donald Trump, 46/42, as of last week. The ups and downs of the presidential race don’t appear to have much down-ballot impact, a trend that we have seen in other states. Trump has lost momentum in Florida over the last week, according to the RCP average, and Hillary has picked up a couple of points from the previous M-D poll in late August.  Rubio has soared over the same period, and now looks all but a sure bet to hold onto his Senate seat.

Even if Donald Trump has hit some roadbumps of late in the presidential race, Democratic hopes of translating a presidential cycle into a Senate win still look bleaker than they should. David Drucker laid it out over the weekend:

This year’s battle for control of the Senate should favor the blue party. The Republicans hold just a five-seat edge, and most of the 34 seats up for election or re-election are in states that are either tossups in the presidential contest or lean to the left.

Yet with a little more than five weeks to go, Republicans are in control of two key Senate races — in swing states Florida and Ohio — and are holding their own in three more crucial contests in the battlegrounds of New Hampshire and Nevada and the blue state of Pennsylvania.

If the Republicans maintain their seats in Florida, Ohio, New Hampshire and Pennsylvania and flip the seat in Nevada left by retiring Senate Minority Leader Harry Reid, their odds of keeping their majority for the next two years rise substantially.

And don’t forget what will be the least surprising November surprise — the rollout of new ObamaCare prices and plans a week before the election, a point I made for The Fiscal Times a few weeks ago. The biggest increases will be mostly in states with competitive Senate races (except Minnesota), and voters will have an immediate method of registering their disgust and contempt for Democrats.