GOP Rep. Mark Sanford of South Carolina tells local reporters in his state that he thinks a path to citizenship will end up in the final immigration bill:

Rep. Mark Sanford believes Congress ultimately will pass an immigration reform bill that contains a pathway to citizenship for millions of undocumented workers already in the U.S.

Although the U.S. House likely won’t take up the entire bill that passed the U.S. Senate, Sanford said the House probably will pass “micro bills that are palatable to the body,” dealing with individual provisions such as high-tech workers and agricultural workers.

But once House and Senate members get together to meld the competing bills into one, Sanford said the pathway to citizenship contained in the Senate version likely will remain, regardless of opposition from conservative congressmen.

“Once it leaves House, I think it will be the Senate side that prevails,” he said Monday.

In other words, if Republicans pass some piecemeal bills that don’t include citizenship, a path will be inserted into the final product in conference negotiations. As I noted here yesterday, reporting from National Review’s Jonathan Strong, who is well connected among House Republicans, indicates that this is actually an outcome many Republicans fear. As a result, many may be reluctant to support even piecemeal provisions they themselves want on enforcement and security, because passing nothing would enable Republicans to avoid having to enter into negotiations later.

That could happen. But Sanford’s comments suggest another possible endgame worth keeping an eye out for. It seems likely that Republicans may end up trying to define citizenship down. If flatly opposing citizenship — and killing the bill as a result — is seen as too politically risky, Republicans may coalesce around a path to citizenship for a few million people — significantly less than half of the 11 million current undocumented immigrants in this country.

In other words, Republicans may support a path to citizenship for many of the DREAMers and for family members of current permanent residents or citizens who cannot currently apply for citizenship — due to penalties — but would be allowed under the Republican version of reform to get on the path. Frank Sharry, the head of pro-immigration America’s Voice, estimates there may be roughly two million or perhaps more in both those categories combined.

The rest of the 11 million might get legal status — but not citizenship.

Republicans could end up calling this whole package a “path to citizenship” and daring Democrats to say No to it. After all, this would suddenly grant legal status and the right to work to 11 million people who currently have no status at all. The theory would be that this would be very hard, ultimately, for Dems to oppose.

It’s anyone’s guess, of course, whether a majority of House Republicans can even get to a place where they can support this version of a “path to citizenship.” But it’s not impossible, and indeed, Sanford’s comments above suggest that some Republicans do think citizenship will be a sticking point that will put them on the defensive in conference, which means they may stake out the lesser version as their very own “path to citizenship.”

All of which is to say that Dems need to be ready for a very tough fight in the next few months — one in which they will have to battle for every inch in the direction of a path to citizenship for the 11 million that they can get.

Greg Sargent writes The Plum Line blog, a reported opinion blog with a liberal slant -- what you might call “opinionated reporting” from the left.