Absolutely, Trump will dominate the Republican Agenda and, for the most part, he will dominate the Democratic Agenda as well, or at least receive more than his fair share of attention. The American people just cannot get enough of his tough and gritty talk. The media is all too ready to give the public what they want and that is more Trump.
Try as we might to ignore him, "the Donald" will likely become the Republicans' nominee for president. This means that, unfortunately, Trump will be able to dominate the Republicans' agenda for quite some time if he is becoming their nominee. The Republicans will be forced to consider him more seriously.
I don't know if I say this because I'm conservative, but I think just the fact alone that Donald Trump is the only one left on the republican side, makes him powerful enough already. He can definitely push the republican agenda and dominate it, even further than he is now.
Donald Trump has garnered an unbelievable amount of support from previously overlooked societal groups, however those groups are part of the vocal minority. Right-wing extremists have fallen in line with Trump's ideals, responding to his claims of "political incorrectness" and the idea of Trump as one "outside of politics." Trump has made great strides in his goal to shake up the establishment in his battle cry of "I'm not a politician", but this has inevitably brought about a response from the more moderate Republicans, whose support flies into any direction but Trump's.