When the history of the current anti-immigration movement in the country is written, January 29th may be seen as a turning point in their fortunes. John McCain, one of the most pro-immigrant politicians in America today (in either party), has moved out ahead of the competition with a clear win in the Florida primary, a state that only allows registered Republicans to participate in their GOP primary. Rudy Guiliani will drop out of the race tomorrow and endorse McCain.

And for those who think somehow voters were duped and didn't really consider immigration, the polls suggest quite the opposite. McCain scored far better on immigration than any other Republican candidate among Republican voters.

For those who thought immigration would be a wedge issue that would be the dominant theme in their campaigns, the McCain win is no doubt troublesome. This is particularly true for GOP candidates already facing a tough year (28 Republican House members have already announced they are not seeking re-election). Will these candidates embrace the pro-immigration  McCain (who has been regularly hissed at campaign stops by anti-immigrant activists)?

This is not to say that the antis are completely finished. They still are scoring victories at the state level and as of now Congress is still too afraid to move on the issue. But the potency of the anti-immigration message is seemingly on the wane, as the Wall Street Journal pointed out yesterday.

I think we'll see some interesting movement on Capitol Hill if McCain gets the nomination. Republicans will not want to embarrass their presidential candidate in the midst of a tough campaign and if Democrats seek to move significant immigration legislation, GOP leaders may feel compelled to hammer out deals quietly and quickly in order to avoid situations where McCain would have to walk the tightrope of pleasing hardliners and not alienating Hispanics who he must convince to support him if he has any chance in November.