Democrats in the Senate went for a mid-course correction on Wednesday, making a major change in how to pay for President Obama's jobs bill, as party leaders endorsed a 5% surtax on those who make more than a million dollars a year in income.

"We're going to move to have the richest of the rich pay a little more," said Senate Majority Leader Harry Reid, who previewed what's sure to be a full blown populist argument for why the wealthy should foot the bill on the Obama jobs bill.

"75 percent of Republicans support this tax," Reid told reporters.

"The problem is none of them are in the Senate."

Republicans didn't need to utter any words in response to the Democratic plan, because they have telegraphed their refusal to accept any tax increases to pay for this plan.

Senate Republican Leader Mitch McConnell accused Democrats and the White House of making the surtax change merely to "sharpen" their political argument.

On the Senate floor, McConnell said "the President is not engaged right now in a good-faith effort to spur the economy or create jobs through legislation."

"He’s engaged in a reelection campaign."

It wasn't clear how many votes Democrats would have in the Senate with the change and whether the surtax would be the only way that revenue is raised to pay for the jobs bill.

While Reid assured reporters that it would cover the entire $448 billion measure, there was no cost estimate or legislative language released.

Reid and other top Democrats were also vague about when the bill would finally come to the floor - next week still seems likely.

So what's the likely future for this measure?

Democrats seem likely to bring their revised bill to the floor in coming days, but it probably won't get 60 votes.

Once that happens, maybe then Republicans in the House will move their own more limited measure - or maybe they will wait to see what the Senate can produce.

Meanwhile, the Congressional Budget Office has weighed in on the spending portion of the President's jobs bill, reporting that it would cost $175 billion.

$50 billion would be spent on transportation infrastructure, $44 billion to extend long term jobless benefits, $30 billion for school repairs and $30 billion to prevent teacher layoffs.

The CBO said it will report on the cost of the tax revenue provisions in the President's plan in coming days, which will drive the cost closer to the $448 billion estimate from the White House.

We'll see what the fine print looks like when Senate Democrats actually put it on the floor - maybe today, tomorrow or next week.