While immigration is barely discussed in the mainstream presidential campaign, a Spanish-language war of accusations continues to play on TV screens in "Hispanic battleground" states.A few days ago, John McCain's campaign launched an ad which again accused Barack Obama of sinking immigration reform in the Senate and also charged the Democrats with running "fraudulent" ads.On Wednesday the Obama campaign will respond with this new ad in Spanish which will air in (you guessed it) Florida, Nevada, New Mexico and Colorado, washingtonpost.com reports. As Politico's Ben Smith notes, the new ad doesn't go so far as to suggest that McCain and Rush Limbaugh are on the same side of the immigration fight, as the Obama campaign did in previous commercials. This time it says McCain "keeps manipulating and lying about immigration. He wants to hide the fact that he was the one who turned his back on us."Then a CNN clip is played (and replayed) of McCain saying at a debate between the Republican primary candidates that he would not vote for his own immigration reform bill. As we noted when the Republican campaign launched their latest ad, it was a bit surprising that the central claim in Spanish-language ads continues to be related to the failed immigration bill of 2006 -- since the Obama campaign could easily do what it's doing now: call McCain on his reversal regarding that bill.The ad finishes by saying,He surrendered to the anti-immigration movement and, with the Republicans, he betrayed our community. If John McCain is not willing to challenge the Republican Party, how is he going to defend us at the White House?To underline this last point, McCain, with a big smile on his face, is shown standing next to President George W. Bush.