You can also use DSP. Hold down the Ctrl key and slip-edit the clip, e.g., it will become shorter if you're going from 95 to 110 BPM (the clip edge shows a yellow line to indicate that you're stretching the clip).
The fidelity will suck because it's a preview. So click on the clip, type A for audiosnap, then under the Offline drop-down menu, select Radius Mix. Bounce the clip, and Sonar will do the offline calculations needed to do a much higher-fidelity version.
This is almost always preferable to doing a groove clip with sustained sounds, or instruments like bass. For percussive clips, like drums, it's often worth taking the time to create a groove clip.
The crucial aspect of groove clips is that they will follow tempo changes. With DSP stretches, you have to re-stretch if the tempo changes.