Republicans are accusing the Democrats of being "political" by trying to pass the DREAM Act and repeal of "don't ask, don't tell" through the National Defense Authorization Act. As far as objections go, this is a weak one -- Republicans are literally objecting to Democrats doing what the people who elected them want them to do, because it might make them happy. That this has strategic political benefits for the Democrats is ultimately irrelevant as to whether or not they should pass it as part of the Defense Authorization bill -- that politicians act in their political interest is you know, how the system works.
One of the typical Republican objections is that these two items are "unrelated" to defense. It should be immediately obvious that any legislation that potentially increases the ranks of the armed forces is "related" to defense, but it's incredibly absurd as an objection to repealing DADT, since the ban on gays and lesbians serving in the military was passed as part of the 1994 Defense Authorization Act. Sen. Susan Collins, who voted DADT repeal out of committee, is now joining a filibuster of the bill because she believes allowing Republicans to add an infinite number of amendments to the bill is actually more important than preventing qualified service members from being discharged. Both Sens. Orrin Hatch and Bob Bennett supported adding the DREAM Act to the 2007 Defense Authorization Act and are now opposed to adding it to this one.
It's beyond absurd for Republicans to object to Democrats pushing these reforms for political reasons. Even if the Democrats' reasons were purely cynical and political, the policies they're supporting can stand on their own merits. Many of the Republicans opposing the DREAM Act and DADT repeal have no reason for doing so other than politics.