Story highlights Some have cited policy agreements with the GOP nominee

(CNN) Donald Trump may be at the top of the Republican ticket, but for some conservatives he is still not the top priority. While Trump has succeeded in consolidating Republican voters, and even brought aboard former rival and detractor Sen. Ted Cruz, some grassroots conservatives are still choosing to focus their resources on down ballot races rather than the battle for the White House.

In order to get a better sense for why some in the conservative grassroots are choosing to stay on the sidelines of the presidential race, CNN's Dana Bash spoke to the leaders of three conservative groups.

"We had concluded after the primary season last year, we didn't have a strong endorsement for him," said David McIntosh, president of Club for Growth, about Trump. McIntosh made clear his group isn't supporting Hillary Clinton, but said they want to "return to our bread-and-butter" and focus extensively on the Senate and House races.

For McIntosh, the decision not to support the Republican nominee came down to policy disagreements, especially on trade, with both presidential candidates. Like others, the Club for Growth president said he sees the Senate and the House as an effective, and important, check-and-balance on any future president.

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