Opinion of Obama among Hispanic voters has vacillated between support and disillusionment at various points in his presidency, and this decision is likely to renew the criticism that he’s been a big tease.
At the same time, it isn’t necessarily clear that this non-action will dampen the enthusiasm of the GOP base. Republicans can still argue that Obama made a political decision to delay action, but he will do so right after the election — which is why voters need send him a message by making sure that his party loses control of the Senate. The move also may energize conservative activists who sense weakness and see regaining the Senate as an opportunity to effectively end the Obama presidency.
As for the prospects of comprehensive immigration reform, there is simply no way that it will happen during the Obama presidency regardless of whether Democrats maintain control of the Senate. The best chance that liberals had for comprehensive immigration reform was actually when President Bush was pushing it and there was enough Republican support to get it across the finish line if Democrats broadly went along. But they didn’t want to give that victory to a weak Republican president, especially when the prospect of regaining power and getting a better deal was so close.