Were I a Democrat in the United States Senate at the moment, I a) wouldn't be sanguine about my party's odds of holding the Senate majority, and b) would be urging someone—anyone—other than Joe Biden and Kamala Harris to run at the top of the Dem ticket. But even without considering the dementia-ridden president and the cackling nutcase VP, the Democrats are facing an uphill climb in the Senate—for now.

The odds are stacked against Senate Democrats this fall, as they try to hang onto their razor-thin majority in November. Not only will they have to defend 22 incumbent seats, many in Republican-leaning states, but they will also have to offset the loss of West Virginia Senator Joe Manchin, who announced his retirement from the Senate last year.

West Virginia is one of the reddest states in the nation and Democrats don't see a path to retain the seat without Manchin. Their best but unlikely hope is to pick up a seat in either Texas or Florida, where Sen. Ted Cruz and Sen. Rick Scott are running for reelection.

There are currently 48 Democrats, plus three independents who caucus with them, giving them a 51-49 majority.

I imagine Joe Manchin isn't very popular with his fellow Democrats right now, but let's face it, he would have lost his re-election bid this year anyway; stepping down was probably the best option he had.

Let's look at a few key states:

Montana: Jon Tester (D-MT), a Democrat in a pretty reliably red state, is surprisingly popular in Big Sky Country. He's likely to retain his seat: net change, 0.

Arizona: Kyrsten Sinema (I-AZ) hasn't said much about running for re-election; Arizona Democrats can't stand her and Arizona Republicans are lining up to run against her. A lot will depend on how Kari Lake handles her campaign. If she wins, that's GOP +1.

Ohio: Sherrod Brown (D-OH) is defending a Senate seat in a state that's gone pretty reliably red. But Brown has a pretty impressive war chest. At this time, I'm calling this one a wash; Net change, 0.

West Virginia: Joe Manchin (D-WV) has bowed out. West Virginia is now reliably Republican. The GOP will likely pick the popular Governor Jim Justice to run for the seat. Net change, GOP +1.

Some of these may end up as nail-biters, particularly Ohio—probably Michigan and Pennsylvania as well. But there are two factors that, I think, outweigh all the others and which may make a big difference in some of these swing states:

1. Immigration. The Senate just passed a perfectly awful immigration bill, which was pronounced dead on arrival in the House. Nothing is likely to be done about this mess before election day, the illegal influx will continue, and if the GOP has any brains at all, they will hang the border crisis around Democrat necks like an anvil.
2. President Biden. He's non compos mentis. He's gone. Checked out. Run down the curtain. Playing Scrabble with only vowels. Half a bubble off plumb. And his understudy, while not senile (a very slim advantage in this case), is unelectable, having all the personal appeal of poison ivy and the intellectual capacity of an opossum.

See Related: Schumer Swoons Over McConnell's Work on 'Border Security' Bill — 'Have Never Worked So Closely' 

Senator Lankford Doubles Down Denying 5,000 Illegals Will Be Admitted Daily No Matter What the Bill Says

November is still a long way away, and a lot can happen between now and then. At this point, it looks like the Senate is the GOP's to lose. But then, we thought that a red wave was coming in 2022, as well, and that turned out to be a red piddle.

We'll see!