The best possible scenario for Democrats tomorrow would be for House Speaker John Boehner’s (R-Ohio) budget proposal to lose, clearing the way for a less-ridiculous compromise. To help ensure that outcome, Dem leaders want to ensure no conservative Democrats help the GOP leadership get a majority.

As of this morning, Greg Sargent reports, Boehner should count on zero Democratic votes.

After aggressively whipping votes, the office of House minority whip Steny Hoyer now believes that not a single Democrat will vote for John Boehner’s debt ceiling plan, delivering a blow to GOP hopes for getting it through the House, a top Democratic aide tells me.

“Hoyer has been whipping against the Boehner bill very hard,” says the aide, who is close to Hoyer’s whipping operation. “No Democrats will vote for it.”

This matters for a couple of reasons. One is political: Boehner would love to say his right-wing plan enjoys “bipartisan” support, and if even one Blue Dog breaks ranks and votes with the GOP, he will.

The other is more practical: zero Democratic votes will make it just a little tougher for the Republican leadership to pass the bill. There are 240 House GOP members, and it’ll take 217 to pass Boehner’s plan. With no Dem support, GOP leaders can lose no more than 23 members.

So, will they? As of this afternoon, the momentum appears to be moving in Boehner’s direction. The Speaker told his caucus this morning, “Get your ass in line,” and by some accounts, House Republicans are doing just that.

House Republicans seem to be rallying behind Speaker John Boehner’s plan for lifting the U.S. borrowing cap.

Several Republicans said they were warming to Boehner’s plan for linking about $1 trillion in budget cuts as the price for raising the debt limit — even though they would like to cut further.

Michigan Rep. Mike Rogers said “we’re moving in his direction in a big way today” as he left a closed-door House meeting.

Whether this is legitimate movement, or the result of an effective p.r. strategy to give the appearance of the House GOP coming together, is unclear. There were, however, a couple of firm Republican “no” votes who conceded to reporters this morning that they’re beginning to buckle to party pressure.

For more on what happens if the House approves Boehner’s proposal, check out our post from this morning.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.