While Donald Trump’s presidential campaign appears to be spinning wildly out of control most days and is potentially cratering from lack of support from GOP voters, Republican senators are trying to maintain some independence in order to weather the storm and keep the chamber in GOP hands.

With the conventions in the rearview mirror, the electoral landscape is settling in search of a new baseline for the general election sprint. Fresh polling conducted after the conventions shows that Trump is hemorrhaging Republican voters and thus getting crushed in the typical presidential swing states.

The good news for the GOP is that polling in the Senate races is still competitive, and so while the presidential race might be slipping away from Republicans for good, the Senate majority is firmly in play, with neither party having a distinct advantage.

[ 2016 Roll Call Election Guide: Senate ]

Prospects have changed enough in two races to warrant a ratings change.

We had the open seat race in Florida rated as Tossup and maintained the rating even after GOP Sen. Marco Rubio decided to seek re-election. He became just another Republican senator seeking re-election in a competitive presidential state with Trump’s baggage at the top of the ticket.

But Rubio starts with a narrow advantage over Democratic Rep. Patrick Murphy in the general election. The congressman starts further back than other Democratic challengers such as Tammy Duckworth in Illinois, Russ Feingold in Wisconsin, or Maggie Hassan in New Hampshire in what will be one of the most expensive races in the country.

We’re changing The Rothenberg & Gonzales Political Report/Roll Call rating of the Florida Senate race from Tossup to Tilts Republican. Of course both Rubio and Murphy have to win their primaries. Any other result on August 30 would prompt another ratings change.

[ As Senate races heat up, the map shifts ]

In North Carolina, GOP Sen. Richard Burr has maintained an advantage over former state Rep. Deborah Ross. But running simultaneously with the polarizing Trump and Republican Gov. Pat McCrory, and the increasingly competitive nature of the state could make the senator’s life more difficult. Burr doesn’t have a lot of room for error and strategists on both sides of the aisle expect a close race.

We’re changing our rating of North Carolina from Leans Republican to Tilts Republican, edging toward the Democrats.

The best news for Democrats is that they may not need to win either Florida or North Carolina in order to win control of the Senate in November.

You can read more analysis of the post-convention Senate landscape in the August 5 issue of The Rothenberg & Gonzales Political Report.